DE102014110424A1 - tire - Google Patents

Abstract

A pneumatic tire has an annular carcass ply (4), a belt layer (5) and a first fiber reinforcing layer (6) arranged so as to cover both end portions (5a, 5b) of the belt layer (5), wherein a reinforcing rubber layer (7) between the first fiber reinforcing layer (6) and the belt layer (5) is disposed in a shoulder region on the one side on which the shoulder region is located on an inside of the vehicle during assembly of the tire, and wherein a second fiber reinforcing layer (8) adjacent to Outside or inside of the first fiber reinforcing layer (6) is arranged in a shoulder region on the other side, on which the shoulder region on the outside of the vehicle, and wherein the peel strength of the reinforcing rubber layer (7) is higher than the peel strength of the belt layer (5 ) and the first fiber reinforcing layer (6).

Description

BACKGROUND OF THE INVENTION

Field of the invention

The present invention relates to a pneumatic tire having a carcass ply provided between a pair of bead portions, a belt layer disposed in the tire diameter direction outside of the carcass ply, and a fiber reinforcing layer arranged to connect both end portions of the carcass ply Belt layer covered at a tire in the outer diameter direction outer side of the belt layer.

Description of the Related Art

There has already been known a pneumatic tire in which a fiber reinforcing layer is disposed on a tire outer circumferential side of a belt layer in a tread portion. As the fiber reinforcing layer, a structure generally used by winding an organic fiber cord, such as fiberglass, is used. As nylon or aramid, is formed substantially in the tire circumferential direction.

There is a case where the fiber reinforcing layer is arranged so as to cover the entire width of the belt layer or also a case where the fiber reinforcing layer is arranged so as to cover only the both end portions of the belt layer. However, the fiber reinforcing layer is disposed so as to cover at least the both end portions of the belt layer, thereby improving the steering stability as well as the durability.

The following Patent Document 1 describes a pneumatic tire in which a fiber reinforcing layer is disposed in a shoulder area located on an inside of a vehicle for the purpose of improving steering stability in a high speed range and suppressing flatness.

However, since the fiber reinforcing layer is disposed only in the shoulder area on the inside of the vehicle, steering stability in a high load area and durability at high speed on an outside of the vehicle are impaired.

Further, in the following Patent Document 2, there is described a pneumatic tire in which a fiber reinforcing layer is disposed only in a shoulder portion located on an outside of a vehicle so as to prevent irregular wear in the shoulder portion without impairing ride quality.

However, since the fiber reinforcing layer is disposed only in the shoulder region on the outside of the vehicle, the durability at high speed on an inside of the vehicle is impaired.

Further, in the below-mentioned Patent Document 3, there is described a pneumatic tire in which rubber strips covering terminal ends of a belt layer are respectively interposed between a fiber reinforcing layer and the both end portions of the belt layer, thereby improving the belt durability in a high load area.

However, since the rubber strips are disposed between the fiber reinforcing layer and the belt layer in the shoulder regions on both sides, steering stability is impaired.

Documents of the prior art

Patent documents

• Patent Document 1: JP 3-096406 A
• Patent Document 2: JP 11-321 231 A
• Patent Document 3: JP 2008-006 890 A

BRIEF DESCRIPTION OF THE INVENTION

The present invention has been made in consideration of the above-described actual conditions, and the object of the present invention is to provide a pneumatic tire in which both good steering stability and durability can be obtained.

MEANS TO SOLVE THE PROBLEMS

To achieve the above object, a pneumatic tire according to the present invention comprises: an annular carcass ply provided between a pair of bead portions; a belt layer disposed in the tire diameter direction outside of the carcass ply; and a first fiber reinforcing layer arranged to cover both end portions of the belt layer at a tire-diameter-direction outer side of the belt layer, wherein a reinforcing rubber layer is interposed between the first fiber reinforcing layer and the belt layer in a shoulder region on the one side where the reinforcing rubber layer is disposed Shoulder region is located on an inner side of the vehicle during assembly of the tire, and wherein a second fiber reinforcement layer in the tire diameter direction adjacent to the outside or the inside of the first fiber reinforcement layer is arranged in a shoulder region on the other side, on which the shoulder region on the outside of the vehicle , and wherein the peel strength of the reinforcing rubber layer is higher than the peel strength of the belt layer and the first fiber reinforcing layer.

A description will now be given of the operation and operation of the pneumatic tire having the structure described above. In the pneumatic tire according to the present invention, since the reinforcing rubber layer having the higher peel strength (ie, peeling is more difficult) than the belt layer and the first fiber reinforcing layer between the first fiber reinforcing layer and the belt layer is disposed in the shoulder region on the one side, the shoulder region is included When the tire is mounted on the inside of the vehicle, separation at the shoulder area on the inside of the vehicle can be suppressed, and durability can be improved.

Since the second fiber reinforcing layer in the tire diameter direction is located adjacent to the outside or the inside of the first fiber reinforcing layer in the shoulder region on the other side where the shoulder region is on the outside of the vehicle when the tire is mounted, the steering stability can be made particularly in a high-range region Improve burden. As a result, the pneumatic tire according to the present invention can achieve both good steering stability and durability.

In the pneumatic tire according to the present invention, the width of the reinforcing rubber layer is preferably equal to or less than one-third of the half width of the first fiber reinforcing layer based on a tire equator.

Steering stability is impaired if the width of the reinforcing rubber layer becomes too large in relation to the overall width of the tire; however, if the width of the reinforcing rubber layer is within the above range, it is very possible to achieve both good steering stability and durability without compromising steering stability.

In the pneumatic tire according to the present invention, the width of the second fiber reinforcing layer is preferably equal to or less than one-third of the half width of the first fiber reinforcing layer based on a tire equator.

A ground contact pressure difference between the inside of the vehicle and the outside of the vehicle becomes large, and steering stability is impaired if the width of the second fiber reinforcing layer becomes too large in relation to the total width of the tire; However, if the width of the second fiber reinforcing layer is within the above range, good steering stability and also high durability without impairing steering stability can be achieved.

In the pneumatic tire according to the present invention, the final number in the second fiber reinforcing layer is preferably equal to or larger than the end number in the first fiber reinforcing layer.

By increasing the end number in the second fiber reinforcing layer disposed in the shoulder region on the outside of the vehicle, the steering stability can be further improved.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings show:

1 a sectional view along a tire meridian for explaining an example of a pneumatic tire according to the present invention;

2 a schematic sectional view for explaining a tread area;

3 a schematic sectional view for explaining a tread portion according to another embodiment;

4 a schematic sectional view for explaining a tread portion according to another embodiment;

5 a schematic sectional view for explaining a tread portion according to another embodiment; and

6 a schematic sectional view for explaining a tread portion according to yet another embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings. 1 shows a schematic sectional view along a tire meridian for explaining an example of a pneumatic tire according to the present invention, wherein the reference numeral CL designates a tire equator. 2 shows a schematic sectional view for explaining a tread portion of the tire; however, cords in the drawing are only shown conceptually, and an actual arrangement density is denser.

A pneumatic tire T is a pneumatic tire having a pair of bead portions 1 ; Sidewall portions 2 extending in the tire diameter direction from the bead areas 1 extend outwards; a tread area 3 in the tire diameter direction with an outer end of each of the sidewall areas 2 connected is; an annular carcass ply 4 that is between the pair of bead areas 1 is provided; a belt layer 5 in the tire diameter direction on the outside of the carcass ply 4 is arranged; and a first fiber reinforcing layer 6 , which is arranged such that it has the two end regions 5a and 5b the belt layer 5 at a tire outer side of the belt layer 5 covered.

Each one of the pair of bead areas 1 is with an annular bead core 1a and with a bead filler 1b provided in the tire diameter direction on the outside of the bead core 1a is arranged and made of a hard rubber material. The carcass ply 4 is formed by a carcass layer formed by arranging a carcass cord which extends in a direction approximately orthogonal to the tire circumferential direction and which is folded over so that both end portions thereof become the bead core 1a and the bead filler 1b enclose. For the Karkassenkord is preferably an organic fiber material such. Polyester, rayon, nylon and aramid, and a steel fiber material.

The belt layer 5 is by a plurality of layers (two layers in the present embodiment) of belt layers 51 and 52 formed by arranging belt cords 5C are formed with an extension inclined to the tire circumferential direction, wherein the respective belt layers 51 and 52 layered so that the belt cords 5C in opposite directions.

In the present embodiment, the width of the belt layer 51 in the tire width direction greater than the belt layer 52 , At the two end areas 5a and 5b the belt layer 5 That is, the present invention is the two end portions of the belt ply having a maximum width in a plurality of the ply layer 5 forming belt layers, and in the present embodiment, it is the two end portions of the belt layer 51 ,

The belt layers 51 and 52 are formed by a plurality of parallel belt cords 5C covered with a belt cover rubber material from both sides. The above called organic fiber material can be called belt cord 5C be used; however, preferably the steel fiber material is used to increase circumferential rigidity.

The first fiber reinforcement layer 6 has a variety of reinforcing cords 6C which extend substantially parallel to the tire circumferential direction. The first fiber reinforcement layer 6 covers the entire belt layer 5 including the two end regions 5a and 5b the belt layer 5 ,

The first fiber reinforcement layer 6 is formed by spirally winding a ribbon-like member around a forming drum by covering the aligned reinforcing cord 6C is formed with a reinforcing topcoat rubber material. Preferably, for the reinforcing cord 6C the organic fiber material used, such as. Polyester, rayon, nylon and aramid.

At least two main grooves running in the tire circumferential direction 31 and 32 are formed in a tread of the pneumatic tire T according to the present invention. In the present invention, shoulder portions S1 and S2 are provided in an area located farther outward in the tire width direction than the main grooves located outermost in the tire width direction 31 and 32 and which is located further inward in the tire width direction than ground contacting ends E1 and E2.

The ground contacting ends E1 and E2 denote the outermost position in the tire axial direction of a ground contacting surface which comes into contact with a road surface when the tire is placed vertically on a flat road surface when mounting the tire on a normal rim and applying normal internal pressure and application a normal load.

The pneumatic tire T according to the present invention is a tire whose mounting direction is set, the mounting direction being set such that an outside area OUTSIDE is directed to an outside of the vehicle, and an inside area INSIDE to an inside of the vehicle directed when the tire is mounted on the vehicle.

The mounting direction on the vehicle is z. B. characterized in that an indication is attached, indicating whether the side wall area 2 of the tire is to be mounted on the inside of the vehicle or on the outside of the vehicle.

In the pneumatic tire T according to the present invention, a reinforcing rubber layer is 7 between the first fiber reinforcing layer 6 and the belt layer 5 in the shoulder region S1 on the one side, on which the shoulder region S1 is located on the inside of the vehicle when tires are mounted.

A second fiber reinforcement layer 8th is in the tire diameter direction adjacent to the outside or inside of the first fiber reinforcing layer 6 in the shoulder region S2 on the other side, on which the shoulder region S2 is located on the outside of the vehicle.

In the present embodiment, an example is illustrated in which the second fiber reinforcing layer 8th in the tire diameter direction adjacent to the outside of the first fiber reinforcing layer 6 is arranged.

In the pneumatic tire T according to the present invention, since the reinforcing rubber layer 7 which has a higher peel strength than the belt layer 5 and the first fiber reinforcing layer 6 between the first fiber reinforcing layer 6 and the belt layer 5 is disposed in the shoulder region S1 on the one side, which is in the mounting of the tire on the inside of the vehicle, a separation on the shoulder region S1 on the inside of the vehicle can be suppressed, and the durability of the tire can be improved.

As the second fiber reinforcement layer 8th in the tire diameter direction adjacent to the outside or inside of the first fiber reinforcing layer 6 in the shoulder area 52 On the other hand, when the tire is mounted on the outside of the vehicle, further, the steering stability can be improved particularly in the high load area.

Moreover, according to the present invention, the pneumatic tire T is particularly advantageous in the case where the tire is mounted in a state on a vehicle in which a negative camber is provided.

The reinforcing rubber layer 7 is formed by a rubber material in band form or sheet form. At the reinforcing rubber layer 7 a peel strength is higher than a peel strength of the belt layer 5 and the first fiber reinforcement layer 6 ,

As the peel strength of the reinforcing rubber layer 7 is higher than the peel strength of the belt layer 5 and the first fiber reinforcement layer 6 , can be a separation between the belt layer 5 and the first fiber reinforcing layer 6 be suppressed at the shoulder area S1.

The peel strength according to the present invention is a value calculated according to the Standard JIS K-6256-2 is measured, with an increasingly higher level of peel strength indicating that peeling is becoming increasingly difficult. Further, since the reinforcing rubber layer 7 is formed only by the rubber material, the peel strength of the reinforcing rubber layer 7 the peel strength of the rubber material to be produced.

Because the belt layer 5 and the first fiber reinforcing layer 6 formed by covering the cord with the cover layer rubber material as mentioned above, likewise give the peel strengths of the belt layer 5 and the first fiber reinforcement layer 6 the peel strengths of the topcoat rubbers.

From the viewpoint of improving the durability, there are a tire-width-direction outer end of the reinforcing rubber layer 7 and a tire-widthwise outer end of the first fiber reinforcing layer 6 preferably within a range of ± 3 mm, preferably coinciding.

The width D2 of the reinforcing rubber layer 7 is preferably equal to or at least greater than the width of the shoulder region S1 in view of improving the durability. Further, the width D2 is the reinforcing rubber layer 7 preferably equal to or less than one third of a half width D1 of the first fiber reinforcement layer 6 on the basis of a tire equator CL, said width being more preferably equal to or less than a quarter.

When the width D2 of the reinforcing rubber layer 7 is greater than one third of the half width D1 of the first fiber reinforcement layer 6 , the rate of the reinforcing rubber layer becomes 7 in relation to the entire tire, thereby causing a reduction in cornering stiffness and further deterioration of steering stability.

The second fiber reinforcement layer 8th has a variety of reinforcing cords 8C which extend substantially parallel to the tire circumferential direction. The second fiber reinforcement layer 8th According to the present embodiment has approximately the same structure as the first fiber reinforcing layer 6 on.

In view of improving the durability, there are a tire-width-direction outer end of the second fiber reinforcing layer 8th and a tire-widthwise outer end of the first fiber reinforcing layer 6 preferably within a range of ± 3 mm, more preferably coinciding.

In view of improving the steering stability in the high load region, the width D3 of the second fiber reinforcing layer 8th preferably equal to or at least greater than the width of the shoulder region S2. Further, the width D3 of the second fiber reinforcing layer 8th preferably equal to or less than one third of the half width D1 of the first fiber reinforcement layer 6 on the basis of the tire equator CL, more preferably equal to or less than a quarter.

When the width D3 of the second fiber reinforcing layer 8th greater than one third of the half width D1 of the first fiber reinforcement layer 6 is, the difference to the width D2 of the reinforcing rubber layer 7 larger, and the ground contact pressure distribution is impaired. This affects the steering stability.

The tire thickness at the ground contacting end E2 of the shoulder region S2 is preferably between 85% and 115% of the tire thickness at the ground contacting end E1 of the shoulder region S1, and more preferably between 90% and 110%. As a result, deterioration of the ground contact pressure distribution can be suppressed.

With a view to the most uniform possible formation of the tire thickness at the ground contact end E1 and the tire thickness at the ground contacting end E2, the thickness of the second fiber reinforcement layer is 8th preferably between 85% and 115% of the thickness of the reinforcing rubber layer 7 , more preferably between 90% and 110%.

Further, in view of making the tire thickness at the ground contacting end E1 as uniform as possible and the tire thickness at the ground contacting end E2, the lamination number at the ground contacting end E1 is preferably equal to the lamination number at the ground contacting end E2 as in the present invention.

The pneumatic tire according to the present invention is the same tire as a general pneumatic tire except that the reinforcing rubber layer is 7 and the second fiber reinforcing layer 8th are provided in the manner described above, and in the present invention, the conventional known materials, shapes and structures can be used.

Further embodiments

• (1) In the above-described embodiment, the first fiber reinforcing layer is 6 arranged so that it covers the entire width of the belt layer 5 covers; however, the first fiber reinforcement layer 6 also be provided such that they only the two ends 5a and 5b the belt layer 5 covered, like this in 3 is shown.
• (2) In the embodiment described above, the second fiber reinforcing layer is 8th from the first fiber reinforcement layer 6 shown separately; however, the second fiber reinforcement layer 8th and the first fiber reinforcing layer 6 also be formed in an integrated manner by a fiber reinforcement layer is folded over and the underlying layer is superimposed, as in 4 is shown.
• (3) The second fiber reinforcing layer 8th is not limited to a single layer, but may be provided such that a plurality of layers are superimposed on each other. For suppressing any deterioration in the ground contact pressure distribution is the second fiber reinforcement layer 8th in addition to the shoulder region S2, preferably also in the shoulder region S1, as shown in FIG 5 is shown. By adding the second fiber reinforcement layer 8th to the shoulder areas S1 and S2 on both sides, the durability and the steering stability can be improved.
• (4) In the embodiment described above, the second fiber reinforcing layer is 8th approximately the same structure as the first fiber reinforcement layer 6 intended; however, the final number (the number of cords per unit width) is in the second fiber reinforcing layer 8th preferably equal to or greater than the final number in the first fiber reinforcement layer 6 like this in 6 is shown.

By increasing the end number of the second fiber reinforcing layer provided in the shoulder region S2 on the outside of the vehicle 8th the steering stability can be improved even further.

Examples

In the following, examples will be described concretely illustrating the construction and operation of the present invention. An evaluation of the respective properties of the tire was carried out as follows. One size of tire tested was size 225 / 40R18, this tire being mounted on a rim with a rim size as defined in the JATMA standard.

(1) Durability at high speed

The load was applied to the tire at the maximum load capacity time, the speed was increased every 10 minutes by 10 km / h in a state where a camber angle of 2 degrees (room temperature 35 ° C) was used, and it The speed at which a defect occurred due to separation at the periphery of the belt end was measured. The evaluation was made by an index number, with a result given as 100 in the conventional example and a higher numerical value indicating a better durability at high speed.

(2) steering stability

The straight-running stability, the lane change behavior and the cornering behavior on a dry road surface were evaluated on the basis of a feeling test by two drivers. The evaluation was made by means of an index number, a result of the conventional example being given as 4 and a higher numerical value indicating a better steering stability.

In the conventional example, the second fiber reinforcing layer was disposed in each of the shoulder regions on both sides, and the reinforcing rubber layer according to the present invention was not provided. In Example 1, the reinforcing rubber layer was provided instead of the second fiber reinforcing layer in the shoulder region on the inside of the vehicle as compared with the conventional example (see FIG 2 ).

Further, in Example 2, the second fiber reinforcing layer was disposed on both sides as compared with Example 1 (see FIG 5 ). In Example 3, the final number of the second fiber reinforcing layer was increased as compared with Example 1 (see 6 ).

In Comparative Example 1, the reinforcing rubber layer and the second fiber reinforcing layer were reversely arranged as compared with Example 1. In Comparative Example 2, the peel strength of the reinforcing rubber layer was lower as compared with Example 1.

In Comparative Example 3, the width of the reinforcing rubber layer was larger as compared with Example 1. In Comparative Example 4, the second fiber reinforcing layer was not provided as compared with Example 1.

The structure of the respective examples is illustrated in Table 1 together with the evaluation results. In Table 1, the peel strength of the reinforcing rubber layer is a value obtained when manufacturing test pieces and performing the peeling test according to FIG JIS K-6256-2 this is illustrated by the index number given as 100 in the case of the peel strength of the belt layer and the first fiber reinforcing layer.

In Table 1, in the arrangement of the reinforcing rubber layer, "inside" refers to an arrangement of the reinforcing rubber layer in the shoulder area located on the inside of the vehicle during assembly of the tire, and "outside" refers to the arrangement of the reinforcing rubber layer in the shoulder area extending when mounting the tire located on the outside of the vehicle.

In Table 1, the width (D2) of the reinforcing rubber layer is illustrated by a rate in a case where half the width (D1) of the first fiber reinforcing layer is set to 100.

The arrangement and the width (D3) of the second fiber reinforcing layer are the same as the arrangement and the width (D2) of the reinforcing rubber layer. The final number in the first fiber reinforcing layer and the second fiber reinforcing layer is a cord number per inch or 2.54 cm in the width direction of the reinforcing cord.

Examples 1 to 3 can achieve both high durability and good steering stability as compared with the conventional example and the comparative examples.

LIST OF REFERENCE NUMBERS

1

bead

2

Sidewall portions

3

Tread area

4

ply

5

belt layer

5a

end

5b

end

5C

belt cords

6

first fiber reinforcement layer

6C

reinforcing

7

Reinforcing rubber layer

8th

second fiber reinforcement layer

8C

reinforcing

31

main groove

32

main groove

51

belt layer

52

belt layer

T

tires

CL

tire equator

E1, E2

Ground contact ends

S1, S2

shoulder areas

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 3-096406A [0010]
• JP 11-321231 A [0010]
• JP 2008-006890 A [0010]

Cited non-patent literature

• Standard JIS K-6256-2 [0048]
• JIS K-6256-2 [0069]

Claims (4)

A pneumatic tire comprising: - an annular carcass ply ( 4 ) between a pair of bead areas ( 1 ) is provided; - a belt layer ( 5 ) in the tire diameter direction on the outside of the carcass ply (FIG. 4 ) is arranged; and - a first fiber reinforcement layer ( 6 ) which is arranged such that it has both end regions ( 5a . 5b ) of the belt layer ( 5 ) at a tire outer side of the belt layer (FIG. 5 ), wherein a reinforcing rubber layer ( 7 ) between the first fiber reinforcement layer ( 6 ) and the belt layer ( 5 ) is arranged in a shoulder region on the one side, on which the shoulder region is located on an inner side of the vehicle during assembly of the tire, and a second fiber reinforcement layer (FIG. 8th ) in the tire diameter direction adjacent the outside or the inside of the first fiber reinforcing layer (FIG. 7 ) is arranged in a shoulder region on the other side, on which the shoulder region is located on the outside of the vehicle, and wherein the peel strength of the reinforcing rubber layer ( 7 ) is higher than the peel strength of the belt layer ( 5 ) and the first fiber reinforcement layer ( 6 ). A pneumatic tire according to claim 1, wherein the width of the reinforcing rubber layer ( 7 ) is equal to or less than one third of the half width of the first fiber reinforcement layer ( 6 ) on the basis of a tire equator. A pneumatic tire according to claim 1 or 2, wherein the width of the second fiber reinforcing layer (16) 8th ) is equal to or less than one third of the half width of the first fiber reinforcement layer ( 6 ) on the basis of a tire equator. A pneumatic tire according to any one of claims 1 to 3, wherein the final number in the second fiber reinforcing layer (14) 8th ) is equal to or higher than the final number in the first fiber reinforcing layer ( 6 ).

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